This one on your left is Chandrayaan 3. Sorry. This one on your right is Chandrayaan 3. It can be confusing, but let's clear your confusion. Today, we will learn about 10 differences between Chandrayaan 3 and 2.
In Chandrayaan 3, there is a science payload called SHAPE, which stands for Spectro Polarimetry of Habitable Planet Earth. This payload is designed to gather the spectrum and polarimetry data of Earth's light polarization. The objective is to understand the unique signature of Earth and determine if the polarimetry and spectrum of other planets are similar.
So, that's one aspect of SHAPE.
Our third difference, we will see from the front image of the lander. Now, you will be able to see it and point out the exact differences. But the main difference is that you can see two circles on the right. That is the TTC antenna of Chandrayaan 3, which stands for telemetry, tracking, and command antenna. This antenna provides us with telemetry data and tracking data. You must have seen that during Chandrayaan 3's landing, all these velocities and data were transmitted. It is called telemetry, and it will be transmitted through this antenna.
There are two antennas on the top of Chandrayaan 3, one in the front and one in the back, possibly for redundancy or for double data rate, though I am not sure. I am mentioning it because if you have just seen the photo of my propulsion model, you must have noticed that there are two TTC antennas on the propulsion model. So, you will observe this when you get more details in the future.
The fourth difference, two circles in the front are looking black on the left of the lander. That is actually the hazard avoidance camera that is near the land. So, it is to check if there are any hazards or big boulders. The interesting thing is that it is also on the top of Chandrayaan 2, but it is not visible. These golden sheets are called MLI, though they are not actually gold. They are hidden under it.
But there are two hazard cameras on Chandrayaan 3. So yes, this is an interesting thing.
How to identify Chandrayaan 3's lander?
Another thing, there is no big difference. You will notice that there are markers on the ramp. These are checker marks that are boxed. This is important because there are some news channels, maybe some newspapers, or even media and YouTube channels that may show images of Chandrayaan 2 as Chandrayaan 3. So, you will know that the biggest difference maker is not on the checker marks in Chandrayaan 2.
But now, we are going back to the original design with some changes to it. It is interesting. So, we have discussed such things for the sixth difference, which was not originally planned but added.
In the seventh difference, we will come to the left side of the right-side lander. It is not used for the things that were made for Chandrayaan 2. It is the opposite of that. And that is the big thing which you can see on the attached side. That is the LDV, which stands for Laser Doppler Velocimeter.
Now, we will get the velocity in different directions of Chandrayaan 3. What does this do? Multiple lasers will create an interference pattern. And we can determine, from the rate of change of this interference pattern, how far we are going back and forth.
What is below that is the laser altimeter. In case you are wondering, it's present on both sides.
If we stay on this side, you will see that the solar panel has grown. If you look at the lander properly, the left part of the lander has a long and big continuous solar panel. That is its ideal. That means the land should be made so that the sun falls maximum on it because it is big and will produce more power.
But in case, if it lands in a different orientation, what will happen? For maximum power generation, that side also increased the solar panel at any angle. And in case you do not know, the back also has solar panels of the lander. So almost every side has solar panels. There were also on Chandrayaan 2, but now this side has increased in Chandrayaan 3.
But what is very good is that we have already taken the image of this landing site. Chandrayaan 2 has a camera on it. Its name is OHRC, which stands for Orbiter High-Resolution Camera. This is the highest-resolution moon camera in the world. I have made a dedicated video on it because of this.
Because of OHRC, we can detect rocks and boulders, even small details. And what is good is that our previous mission has already been scouted for our next mission. And we have seen that it will land safely. Very, very cool.
Different Stack Configuration
First comes the stack. There was a lander named Vikram in Chandrayaan 2, and an orbiter. There were science instruments on the orbiter. The orbiter took the lander to the moon from the Earth. Then the lander landed on the moon. Now the landing failed, that's fine. But our orbiter is still roaming and gathering science.In Chandrayaan 3, the stack does look a bit similar. This orbiter is mostly a propulsion module because it has mostly fuel. And its work is to take Chandrayaan 3's lander from the earth to the moon. The lander may or may not be Vikram, don't know. Then it will separate it.
Does it mean that there is no experiment on Chandrayaan 3 on the orbiter? There is one experiment. And this comes as our second difference.
Does it mean that there is no experiment on Chandrayaan 3 on the orbiter? There is one experiment. And this comes as our second difference.
Chandrayaan 3 orbiter is low in Experiment
Chandrayaan 2's experiment suite was one of the best in the world, many first-time-ever experiments on the moon.In Chandrayaan 3, there is a science payload called SHAPE, which stands for Spectro Polarimetry of Habitable Planet Earth. This payload is designed to gather the spectrum and polarimetry data of Earth's light polarization. The objective is to understand the unique signature of Earth and determine if the polarimetry and spectrum of other planets are similar.
So, that's one aspect of SHAPE.
Chandrayaan 3 lander changes
Our third difference, we will see from the front image of the lander. Now, you will be able to see it and point out the exact differences. But the main difference is that you can see two circles on the right. That is the TTC antenna of Chandrayaan 3, which stands for telemetry, tracking, and command antenna. This antenna provides us with telemetry data and tracking data. You must have seen that during Chandrayaan 3's landing, all these velocities and data were transmitted. It is called telemetry, and it will be transmitted through this antenna.
There are two antennas on the top of Chandrayaan 3, one in the front and one in the back, possibly for redundancy or for double data rate, though I am not sure. I am mentioning it because if you have just seen the photo of my propulsion model, you must have noticed that there are two TTC antennas on the propulsion model. So, you will observe this when you get more details in the future.
Moar camera in Chandrayaan 3
The fourth difference, two circles in the front are looking black on the left of the lander. That is actually the hazard avoidance camera that is near the land. So, it is to check if there are any hazards or big boulders. The interesting thing is that it is also on the top of Chandrayaan 2, but it is not visible. These golden sheets are called MLI, though they are not actually gold. They are hidden under it.
But there are two hazard cameras on Chandrayaan 3. So yes, this is an interesting thing.
How to identify Chandrayaan 3's lander?
Another thing, there is no big difference. You will notice that there are markers on the ramp. These are checker marks that are boxed. This is important because there are some news channels, maybe some newspapers, or even media and YouTube channels that may show images of Chandrayaan 2 as Chandrayaan 3. So, you will know that the biggest difference maker is not on the checker marks in Chandrayaan 2.
More fuel in Chandrayaan 3
The fifth difference that many of you must have seen in this image is a big tank. The dome in the center is actually for the fuel tank engines. And if it is a little big in this case, then it may be carrying more fuel. Now, it is interesting to carry more fuel because it leads to the sixth difference.
No central engine in Chandrayaan 3
The center engine was removed. So, in Chandrayaan 3's specification sheet, there are four engines. Now, this is interesting because there were four engines in the original design of Chandrayaan 2. However, in 2018-2017, as you may know, there was a lot of chaos at the last minute. When Annadurai sir retired, he was not the Mission Director but was involved in the development of Chandrayaan 1. So suddenly, the fifth engine was added, resulting in extra fuel, as it had to mitigate the dust blowback from the fifth engine.But now, we are going back to the original design with some changes to it. It is interesting. So, we have discussed such things for the sixth difference, which was not originally planned but added.
Lasser
In the seventh difference, we will come to the left side of the right-side lander. It is not used for the things that were made for Chandrayaan 2. It is the opposite of that. And that is the big thing which you can see on the attached side. That is the LDV, which stands for Laser Doppler Velocimeter.
Now, we will get the velocity in different directions of Chandrayaan 3. What does this do? Multiple lasers will create an interference pattern. And we can determine, from the rate of change of this interference pattern, how far we are going back and forth.
What is below that is the laser altimeter. In case you are wondering, it's present on both sides.
Bigger Solar Panel and more power in Chandrayaan 3
If we stay on this side, you will see that the solar panel has grown. If you look at the lander properly, the left part of the lander has a long and big continuous solar panel. That is its ideal. That means the land should be made so that the sun falls maximum on it because it is big and will produce more power.
But in case, if it lands in a different orientation, what will happen? For maximum power generation, that side also increased the solar panel at any angle. And in case you do not know, the back also has solar panels of the lander. So almost every side has solar panels. There were also on Chandrayaan 2, but now this side has increased in Chandrayaan 3.
Chandrayaan 3 landing site
The ninth point is that our landing site has changed a little. First, it was going to land at 70 degrees, 22 degrees. Now, it will be 69,32.
But what is very good is that we have already taken the image of this landing site. Chandrayaan 2 has a camera on it. Its name is OHRC, which stands for Orbiter High-Resolution Camera. This is the highest-resolution moon camera in the world. I have made a dedicated video on it because of this.
Because of OHRC, we can detect rocks and boulders, even small details. And what is good is that our previous mission has already been scouted for our next mission. And we have seen that it will land safely. Very, very cool.
Chandrayaan 3 Software
There will be a 10th and last difference in software. Look, till now, there has not been a detailed reason or a detailed post-mortem of Chandrayaan 2. Even in the parliament, there was mention of a software issue. However, recently, SSLV published a long document explaining what exactly happened. So, we now know that there was some glitch in the software.Don't forget to comment. Thank You